A cerebrovascular disease, which typically causes a stroke, occurs suddenly and is accompanied by symptoms such as loss of consciousness, quadriplegia, and loss of speech. In many cases, the disease progresses rapidly in a short time. If one has a stroke, he/she is highly likely to die. Even if he/she does not die, it leaves him/her severely disabled. Therefore, he/she cannot lead a normal life in many cases. Also, the cerebrovascular disease is the second most common cause of death after cancer. It is reported that 75 per 100,000 people die of strokes and about 200 per 100,000 people a year suffer a stroke.
Cerebrovascular diseases are roughly classified into an obstructive cerebrovascular disease and a haemorrhagic cerebrovascular disease. The obstructive cerebrovascular disease refers to damage to the brain mainly due to occlusion of a cerebral artery caused by various reasons, and the haemorrhagic cerebrovascular disease refers to a cerebral haemorrhage caused by the rupture of a blood vessel in the brain.
A representative lesion that causes the haemorrhagic cerebrovascular disease among the above-described two kinds of cerebrovascular diseases is a cerebral aneurysm. If a cerebral aneurysm ruptures and progresses to subarachnoid hemorrhage, it may cause severe brain damage and lead to severe and even lead to death. Therefore, it is necessary to treat a cerebral aneurysm, which can rupture anytime, in advance in order to protect the life of a patient.
As a treatment method for cerebral aneurysm, direct surgery such as aneurysm neck ligation has been performed. The aneurysm neck ligation is direct craniotomy and has been most commonly performed for years. However, the direct surgery is painful to patients and highly limited in surgery site. In order to solve this problem, a minimally invasive treatment method called coil embolization of filling the inside of cerebral aneurysm using a platinum coil has been performed. However, when the coil embolization is performed, it is necessary to insert a stent formed as a metal mesh suitable for the shape of aneurysm neck in order for the coil not to poke out after the coil embolization. Actually, in many cases of cerebral aneurysm, the aneurysm neck is wide, which is referred to as a wide-neck aneurysm or giant-neck aneurysm. If such an aneurysm occurs, insertion of a stent is inevitable in order to suppress a coil for embolization not to poke out and to readily induce embolus of a cerebral aneurysm.
In order for a subsidiary stent for embolization to stably reach the affected area after being inserted into the body, the subsidiary stent needs to pass through a narrow and tortuous blood vessel of the brain. Also, in order for a coil inserted into a cerebral aneurysm not to deviate and to withstand blood pressure, the coil needs to have excellent properties such as flexibility and radial resistance.
Further, markers formed of a material having high radio-opacity need to be attached to the beginning and the end, respectively, of the stent.
The marker precisely shows a position of the stent on the X-ray, so that an operator can deploy the stent at an accurate position and also easily manage the stent after the embolization.
Stents can be classified into vascular stents and non-vascular stents depending on a target in which a stent is used. The vascular stents can also be classified into a coronary artery stent used for cardiovascular stenosis, a peripheral vascular stent, and a cerebrovascular stent.
The background technology of the present disclosure is disclosed in Korean Patent Laid-open Publication No. 10-2012-0132368.